The present disclosure relates generally to a refrigeration system for use in a refrigeration device (e.g. temperature controlled case, refrigerated storage unit, merchandiser, cooler, etc.). The present disclosure relates more particularly to a refrigeration system that is suitable for use with refrigeration devices configured to operate between a first cooling mode (e.g., low temperature cooling mode, etc.) and a second cooling mode (e.g., medium temperature cooling mode, etc.). The present disclosure relates more particularly to a control module of the refrigeration system and a method of controlling temperature within the refrigeration device depending for various cooling modes.
It is generally known to provide refrigeration devices (e.g., temperature controlled cases, refrigerated storage units, merchandisers, coolers, etc.) having a refrigeration system for circulating a refrigerant or coolant through one or more cooling elements within the device to maintain items (such as food products and the like) within a certain desirable temperature range. The desirable temperature range will vary depending on the type of items that are received by the refrigeration device. Refrigeration devices are often distinguished by those skilled in the art of commercial refrigeration as being either a “low temperature” refrigeration device or a “medium temperature” refrigeration device. Low temperature refrigeration devices are generally used to display or otherwise support items including, but not limited to, frozen food products or partially frozen food products. Medium temperature refrigeration devices are generally used to display or otherwise support items including, but not limited to, fresh food products.
To maintain items within the refrigeration device at the desirable temperature range, refrigeration systems typically include a control module configured to regulate the positioning of a throttle device to modulate the flow of refrigerant that is supplied to the cooling elements. Based upon signals received from various sensing devices, the control module compares a value representative of an actual reading within the refrigeration device with a predetermined reference value and regulates the positioning of the throttle device accordingly to modulate the flow of refrigerant.
In conventional control modules, only a single predetermined reference value for regulating the position of a throttle device may be inputted by a user and/or manufacturer (e.g., either a predetermined reference value for a low temperature refrigeration device or a predetermined reference value for a medium temperature refrigeration device, etc.). Since the predetermined reference value is different for a low temperature refrigeration device and a medium temperature refrigeration device, a different control module is required for each application.
For certain applications, it may be desirable to change the cooling mode at which the refrigeration device is operating (e.g., convert a low temperature refrigeration device to a medium temperature refrigeration device, convert a medium temperature refrigeration device to a low temperature refrigeration device, etc.). If the refrigeration device is equipped with a conventional control module, the user must add and/or replace a control module in order to complete the conversion process. Adding and/or replacing a control module may increase the expense and/or time required to convert the refrigeration device between a refrigeration device configured to operate at a different cooling mode.
Accordingly, it would be desirable to provide a refrigeration system that can operate between a first cooling mode (e.g., a low temperature cooling mode, etc.) and a second cooling mode (e.g., a medium temperature cooling mode, etc.) without requiring a separate control module for each cooling mode. It would also be desirable to provide a refrigeration system having a control module that is configured to determine whether the refrigeration system is operating within a first cooling mode and a second cooling mode. It would be further desirable to provide a refrigeration system having a control module that is configured to determine whether the refrigeration system is operating within a first cooling mode and a second cooling mode without requiring any manipulation by a user. It would be further desirable to provide a refrigeration system having a control module that modulates the flow of refrigerant through a cooling element. It would be further desirable to provide a refrigeration system that regulates a throttle device (such as a superheat valve) to modulate the flow of refrigerant during the cooling mode. It would also be desirable to provide a refrigeration system having a control module capable of applying a first predetermined setpoint for regulating the throttle device in the first cooling mode and applying a second predetermined setpoint for regulating the throttle device in the second cooling mode.
Accordingly, it would be desirable to provide a refrigeration system for a temperature controlled case having any one or more of these or other desirable features.